The present invention relates generally to stabilizers for use in motor vehicles, and more particularly to a stabilizer control apparatus for accurately and surely controlling the stabilizers during such conditions as turning of the motor vehicle in order to ensure comfortable and stable vehicle running.
Motor vehicles are generally equipped with stabilizers in order to reduce inclination and rolling of the vehicle bodies during such running conditions as turning and irregular-road-running of the motor vehicles. An important problem arising in the use of the stabilizers is, however, that the stabilizer is coupled between a left-side wheel and a right-side wheel of the motor vehicle so as to restrict the independent movements of the left-side wheel and right-side wheel to make greater vibration of the motor vehicle, thereby resulting in incomfortable ride of the motor vehicle. In order for removing such a problem a control apparatus for allowing control of the twisting force of the stabilizer has been proposed such as is disclosed in Japanese Patent provisional Publication No. 61-146612, in which the twisting-force control is performed in accordance with a turning lateral acceleration estimated as a function of wheel speeds and steering amount of the motor vehicle. However, such a prior art control apparatus is required to determine a reference position of a hydraulic-pressure operable piston in a cylinder used for twisting the stabilizer and the appropriate determination of the reference position thereof is difficult because of being greatly varied in accordance with the loading states of the motor vehicle, thereby causing unstable movement of the motor vehicle in conditions such as vehicle turning.